Hi all, The JIRA at OOZIE-1817 <https://issues.apache.org/jira/browse/OOZIE-1817>wants to make the instrumentation timers biased; that is, to make them look only at the last X amount of time, instead of forever. When trying monitoring Oozie, if your Oozie server has been running a long time, they become less useful.
While looking at some of the instrumentation code, I also saw that in a lot of places, we create and use a timer (i.e. a Cron object), but we never add it to the Instrumentation, so it's never actually reported to the user, and is essentially wasteful and useless. We haven't really touched our instrumentation code in a while, and I was thinking it might be a good idea to switch to using a library like Codahale Metrics (also called Yammer Metrics). They include a bunch of stuff for us (e.g. JVM and servlet metrics) and do all of the math for computing standard deviation, percentiles, etc. It also looks like most of the metric types can be upgraded more immediately, instead of every minute. Their API looks pretty similar to what we already have, so it shouldn't be too hard to switch over. Their "Getting Started" page is here if you want to see more about it: http://metrics.codahale.com/getting-started/ We'd have to keep the current Instrumentation for Oozie 4.x, but we could add a /v2/metrics URL for the new one and deprecate the old one. Thoughts? thanks - Robert
